ARHGEF12 and acute myeloid leukemia: Finally, the bipartite Rac1 GEF composed of Dock180 and ELMO1 is overexpressed in malignant gliomas, where it contributes to invasion,63 whereas LARG (leukemia-associated Rho GEF) is found fused with the MLL locus in acute myeloid leukemia (AML)64 leading to aberrant expression.